Vinokourov L.V.
Saint-Petersburg Scientific-Research Institute For Physical Culture, St. Petersburg

Lebedeva A.L.
Saint-Petersburg Scientific-Research Institute For Physical Culture, St. Petersburg

Baymuratov I.A.
Institute for Retraining and Advanced Training of Specialists in Physical Culture and Sports, Nukus Branch, Nukus (Uzbekistan)

Kaipov J.A.
Institute for Retraining and Advanced Training of Specialists in Physical Culture and Sports, Nukus Branch, Nukus (Uzbekistan)

Objective of the study is to identify and describe the mechanism of underwater wave-like swimming movement in swimmers with unilateral lower limb deficiency.
Methods and structure of the study. The underwater phase of the start was videotaped and the video materials were analyzed, the method of stereoscopic analysis of movements with the measurement of the speed of liquid flows and vortex formation, the assessment of the range of rotation of the leg joints, mathematical and statistical methods were used.
Results and conclusions. It was found that the mechanism of movement in the underwater phase after the start in a swimmer with a lower limb deficiency differs from that in healthy swimmers in that it is not able to generate paired vortices and moves due to the release of a vortex created by only one leg. In this case, a large vortex around the foot is created during a downward kick, and a small one - during an upward kick. The range of hip rotation movements in a swimmer with an amputated leg is less than in healthy swimmers.

Keywords: underwater wave swimming, underwater start phase, sports for people with musculoskeletal disorders, paraswimmer, lower limb deficiency.

References

1. Belousov S.I., Vinokurov L.V. Primenenie svetodiodnyh indikatorov dlya videoregistratsii i korrektsi i elementov sportivnoy tekhniki plavaniya v sporte slepyh [Application of LED indicators for video recording and correction of elements of sports swimming technique in blind sports]. Adaptive physical education. 2020. Vol. 82, No. 2. pp. 35-­36.
2. Vinokurov L.V. Spetsialnye zadachi v obshhey psihologicheskoy podgotovke sportsmenov­paralimpiytsev [Special tasks in the general psychological preparation of Paralympic athletes]. Innovatsionnye tekhnologii v sisteme sportivnoy podgotovki, massovoy fizicheskoy kultury i sporta: Sbornik materialov Vserossiyskoy nauchno­prakticheskoy konferentsii s mezhdunarodnym uchastiem, St. Petersburg, October 17­18, 2019. St. Petersburg: FGBUSPbNIIFK, 2019. pp. 28-­32.
3. Mosunov D.F. Voprosy primeneniya vihrevyh dvizheniy zhidkosti v sportivnom plavanii [Application of vortex motions of liquid in sports swimming]. Voprosy sovershenstvovaniya tekhniki plavaniya I metodiki sportivnoy trenirovki plovca: sbornik nauchnyh trudov. NGU im. P.F. Lesgafta. Leningrad, 1972. pp. 34-­35.
4. Patent na poleznuyu model № 203250 U1 Rossiyskaya Federatsiya, MPK A63B 69/10. Svetovoy indicator polozheniya segmentov tela v vode dlya obucheniya sportivnomu plavaniyu: №2020136093: zayavl. 03.11.2020: opubl. 29.03.2021. S.I. Belousov, D.F. Mosunov, L.V. Vinokurov [i dr.]; zayavitel FGBU SPbNIIFK.
5. Hochstein S., Blickhan R., Vortex re­capturing and kinematics in human underwater undulatory swimming. Human Movement Science. 2011. Vol.30, Issue 5. pp. 998–007.
6. Imamura N., Matsuuchi K. Relationship between vortex ring in tail fin wake and propulsive force. Experiments in Fluids. 2013. Vol. 54, Issue 10. Article № 1605.
7. Matsuda Y., Kaneko M., Sakurai Y., Akashi K., Yasuo S. Three­dimensional lower­limb kinematics during undulatory underwater swimming. Sports Biomechanics. 2021. Vol. 23, Issue 11. pp. 1­15.
8. Nakazono Y., Shimojo H., Takagi H., Sengoku Y., Tsunokawa T. Underwater undulatory swimming propulsion mechanism of left lower limb deficient swimmer using PIV method. XIV International Symposium on Biomechanics and Medicine in Swimming Proceedings [Witt M., editors]. Leipzig: evoletics Media. 2023. pp. 353–358.
9. Shimojo H., Gonjo T., Sakakibara J., Sengoku Y., Sanders R., Takagi H. A quasi three­dimensional visualization of unsteady wake flow in human undulatory swimming. Journal of biomechanics. 2019. Vol. 93. pp. 60-­69.